The invention relates to gas flow in aid of the arc discharge of an electric-arc discharge device, wherein the arc discharge is established to a workpiece which is electrically conductive.
Cutting and gouging are common uses of electric-arc discharge devices. With some processes, to do a clean piece of work has been almost impossible due to accumulation of dross products on the workpiece. Efforts to avoid this problem have involved use of gas jets, variously arranged, depending upon the job to be done. For example, to gouge a channel on the exposed face of a workpiece, plural gas jets have been clustered beneath the electrode tip of the device, the jets being directed at the region of arc discharge to the workpiece, all in the hope and expectation of removing a maximum quantity of arc-melted metal. However, as a practical matter, whether the plural jets are clustered beneath the electrode, or circumferentially distributed around the electrode, as in Bulgarian Pat. No. 51,405, published Feb. 15, 1983, the arc discharge is noisy and the worked product is encumbered by dross which includes hardened droplets of melt of workpiece material, strongly adhered to the workpiece, or excessive fuming is encountered. And this is so even when operating the torch with a consumable, automatically fed electrode, whereby to enhance the ability to develop thermal energy at the point of arc delivery to the workpiece; a discussion of such consumable electrodes is contained in pending patent applications Ser. Nos. 780,031 and 780,033, filed Sept. 25, 1985.